When referred to in an environmental permit, these rules will allow the operator to discharge up to 1000 cubic metres per day of water from a cooling circuit or heat exchanger to inland surface freshwaters, coastal waters or relevant territorial waters (as defined in Section 104 of the Water Resources Act 1991), provided that no polluting chemicals are present in the discharge, the temperature change between the inlet and outlet is less than eight degrees Celsius and the outlet temperature does not exceed twenty five degrees Celsius.
This introductory note does not form part of these standard rules.
Note that heating discharges from single houses do not require a permit.
The discharge must be to the same water body from which the water was abstracted but not within 200 metres of another cooling or heating discharge.
The discharge must not be made into ponds or lakes or freshwater within 500 metres upstream from a designated shellfish water, European Site, Ramsar site, Site of Special Scientific Interest (SSSI), National Nature Reserve, Local Nature Reserve or any body of water identified as containing a protected species or within 100 metres from a Local Wildlife Site.
Also, the discharge must not be made to a watercourse at a point where salmon spawn.
For a site in tidal water, ‘500 metres upstream’ means within 500 metres by the shortest distance over water in any direction from the nearest boundary of any of these sites. This restriction only applies to conservation sites that are water-based and linked to the receiving water downstream of the discharge point.